Earthquake Sound P8 User Manual

Control Panel Overview

(4) Power Status LED

(5) Line Level RCA Inputs

(6) Sub Operation Switch

(7) Auto ON/OFF

(8) Speaker Level Inputs

(9) Speaker Level Outputs

(10) Manual ON/OFF Switch

(11) 110-120V AC Power Connection 

Line Fuse

( ) 

3 0-180° Phase Shift 

( ) 
Frequency Adjustment 

2 50Hz - 160Hz

(1) Volume Control 

The LED will light red when the amplifier is in standby 

(1) Volume Control

mode and green when the amplifier is on and 

Manual volume control to regulate your subwoofers 

receiving a signal.

power output, to prevent clipping and distortions 
caused by overpowering.

(5) Line Level RCA Inputs

Connect with RCA type patch cords to the line level 

(2) 50Hz - 160Hz

output of your receiver or pre-amp.

Frequency Adjustment

If your pre-amplifier or receiver has a single sub/LFE 

This

 

controls the high frequency cutoff point. With the 

output, connect it to the subwoofer's left input jack. 

control set to the middle, the subwoofer will reproduce 
frequencies up to 105Hz. If the control is set fully 

There is no need to use the subwoofers right input 

clockwise, the crossover is bypassed and the 

jack. If you want to run your main/satellite speakers 

subwoofer will reproduce a wide frequency range. 

full range, use a "Y" adapter at the pre-amplifier 

With the control fully counter-closkcwise the 

outputs.

subwoofer reproduces a narrow range, up to 50Hz.

In this way, you can send the pre-amplifier's output 

Rotate the control until the bass sound natural. If the 

signal to your main amplifier and to the subwoofer at 

mid-bass sounds natural but you want more low bass, 

the same time.

turn the control down a little.

(6) Sub Operation Switch

(3) 0-180° Phase Shift

In LFE position, the Frequency adjustment becomes 

This control is used to acoustically match the 

disabled and the subwoofer runs in a Full range 

subwoofer’s output to your main speakers. Select the 

mode, from 20Hz - 2kHz. 

position, either 0° or 180°, in which your subwoofer 
has more output at the listening position.

While in Sub position the subwoofer reverts to the 
manual frequency adjustment, allowing the user to 
operate and fine tune the subwoofer to their personal 

(4) Power Status LED

taste.

Earthquake powered subwoofers have an LED on the 
panel that indicates the status of the built-in amplifier.